Graphics features

I added most of the graphics features, There are still a few I would like to fix but most of the are implemented now. Here is list with the ones I added:
* [love.graphics.newStencil]()
* [love.graphics.setLine](http://www.love2d.org/wiki/love.graphics.setLine)
* [love.graphics.setPoint](http://www.love2d.org/wiki/love.graphics.setPoint)
* [love.graphics.drawq](http://www.love2d.org/wiki/love.graphics.drawq) (love.graphics.draw is missing yet but I'll implement it too)
* [love.graphics.quad](http://www.love2d.org/wiki/love.graphics.quad)
* [love.graphics.triangle](http://www.love2d.org/wiki/love.graphics.triangle)
* [love.graphics.setDefaultImageFilter](http://www.love2d.org/wiki/love.graphics.setDefaultImageFilter) / [love.graphics.setDefaultFilter](http://www.love2d.org/wiki/love.graphics.setDefaultFilter)
* [love.graphics.getDefaultImageFilter](http://www.love2d.org/wiki/love.graphics.getDefaultImageFilter) / [love.graphics.getDefaultFilter](http://www.love2d.org/wiki/love.graphics.getDefaultFilter)